Filed of the Invention
The present invention relates to preservation of farm produce and, more particularly, to a method of preserving Ziziphus jujuba and to a liquid preservative used in the method.
Description of the Related Art
Without preservation, Ziziphus jujuba will undergo dehydration and lose more than 5% of its weight in the initial 24 hours after being harvested. Dehydration will cause decomposition, accumulation of ethanol and ethylene, and loss of vitamin C. Without preservation, Ziziphus jujuba will lose its freshness in 2 or 3 days, and will rot and become unsellable in 5-7 days.
Conventional methods for preserving Ziziphus jujuba increase storability to about 1-3 months and the need for an improved method for preserving Ziziphus jujuba is long-felt, but unmet.
Phase temperature is a temperature lower than 0° C. and higher than the freezing temperature of an organism. Preservation of farm produce at such temperature can minimize cellular respiration even when the farm produce is fully mature, which effectively extends its shelf life.
Fruits are preferably preserved at their freezing temperature or at a temperature 0.1-0.15° C. higher than their chilling injury temperature, i.e., at preservation temperatures close to the phase change temperature of the cellular membrane of the fruits.
Phase temperature and controlled atmosphere means a combination of a phase temperature technique and a controlled atmosphere. The temperature fluctuation in conventional cold storage or conventional controlled atmosphere storage for fruits is larger than ±0.5° C., and the preservation temperature thereof is 0.5-1.5° C. higher than the freezing temperature or chilling injury temperature of the fruits, while the temperature fluctuation in phase temperature and controlled atmosphere is smaller than ±0.1° C.
Prior to this invention, there have been no reports of using phase temperature and controlled atmosphere to preserve Ziziphus jujuba. 